As he flew out of Australia for the famed Vietnamese seaside city of Danang, Mr Turnbull said he plans to focus on economic opportunity and regional security during a five-day trip to Vietnam, Hong Kong and the Philippines.

More than 600,000 Rohingya Muslims have fled a brutal campaign of ethnic cleansing in Myanmar's Rakhine State in 11 weeks, the largest movement of civilians in Asia since the Khmer Rouge genocide of the 1970s.

The world's worst humanitarian emergency is unfolding in Rohingya refugee camps at the Bangladesh border.

In the Philippines, more than 14,000 mostly urban poor Filipinos have been killed in President Rodrigo Duterte's so-called "war on drugs," the largest number of civilian deaths in Asia since the 1970s.

In Cambodia, strongman Hun Sen has embarked on a campaign to destroy the country's main opposition party and silence his critics in the worst crackdown on democracy and political freedoms in the country for a decade.

Mr Turnbull will rub shoulders with Mr Duterte, Myanmar's de factor leader Aung San Suu Kyi and Mr Hun Sen at the Asia-Pacific Economic Cooperation (APEC) leaders' summit in Danang, and the Association of Southeast Asian Nations (ASEAN) summit and the security-focused East Asia Summit in the Philippines.

Mr Turnbull will also be in the company of Malaysia's leader Najib Razak who is at the centre of the world's largest corruption scandal involving his country's sovereign wealth fund 1Malaysia Development Corporation Berhad (1MDB).

Also attending the meetings will be Thailand's former military chief and now prime minister Prayuth Chan-ocha who led to coup to topple a democratically elected government in 2014, after months of political instability, and has refused to set a date for fresh elections.

Phil Robertson, Deputy Asia Director at Human Rights Watch, said leaders attending the summits, including Mr Turnbull, will likely "look the other way and act like it's someone else's business to clean up amid what can be only described as a disastrous year for human rights in south-east Asia."

"Watch APEC and ASEAN do a vanishing act by failing to discuss seriously any of the human rights issues," Mr Robertson said.

"Just when leadership on human rights is needed most, the region is confronted by an equally staggering deficit of political leadership and courage to take on these crises," he said.

The Turnbull government has resisted growing calls to cut military ties with Myanmar in response to atrocities committed by security forces in Rakhine that human rights groups say could amount to crimes against humanity under international law.

The government's response to the Philippine killings has been muted while Australia sends troops and boosts intelligence sharing with the country following a four-month siege of the southern Philippine city of Marawi by Islamic State-allied militants, which has prompted fears the terror group could gain a foothold in the region.

Mr Duterte, a blunt-speaking former provincial mayor, could throw a political hand grenade at the APEC summit, saying before arriving in he planned to ask China to make clear its intentions in the flashpoint waters of the South China Sea.

China strongly opposes discussion of the dispute in regional forums.

Mr Duterte told reporters he would bring the dispute to the surface in Danang.

"You want to control the passage or do we have passage?" he said, referring to China.

Mr Turnbull said the APEC meeting attended by leaders of 21 Pacific Rim countries will be an important opportunity to explore ways of growing trade, generating jobs and fuelling economic growth.

He said he hopes agreement can be reached on the Trans Pacific Partnership (TPP) trade deal that was ditched by US President Donald Trump.

In Danang officials and foreign ministers from 11 countries have been discussing pushing ahead with the deal ahead of the arrival of their leaders.

But several countries, including Canada and Malaysia, are showing less appetite to move ahead quickly with the deal that aims to eliminate tariffs on industrial and farm products across a bloc whose trade totalled US$356 billion last year.

The deal is seen as a counterweight to China's growing dominance across the region.

Mr Turnbull said leaders attending the East Asia Summit in the Philippines "will have frank discussion about regional security issues - particularly the unacceptable threat posed by North Korea, but also maritime security and terrorism."

Some Asian leaders have called on Mr Trump and North Korean dictator Kim Jong-un to tone down their threats to annihilate each other's country.

Mr Turnbull will also travel to Hong Kong at the weekend where he will discuss negotiations on an Australian-Hong Kong free trade deal and meet with business leaders.

US President Donald Trump, China's leader Xi Jinping and Russia's Vladimir Putin will be among leaders attending the summits.